Recent activity

The geomagnetic field was quiet on July 22. Solar wind speed ranged between
270 and 356 km/s (all day average 306 km/s - increasing 33 km/s over the
previous day).

Solar flux measured at 20h UTC on 2.8 GHz was 73.6. The planetary A index
was 4 (STAR Ap - based on the mean of three hour interval ap
indices: 4.0).
Three hour interval K indices: 12111112 (planetary), 22111102 (Boulder).

The background x-ray flux is at the class A4 level.

At midnight there was 1 spotted region on the visible solar disk. The solar flare activity
level was very low. No C class events were recorded during the day.

New region 10901 rotated into view at the northeast limb. Polarity
separation is poor and C flares are possible.

Another cycle 24 dipole emerged during the afternoon and was located at
S32E03 at midnight. No spots have been observed so far.

Coronal mass ejections (CMEs)

July 21-22: No partly or fully Earth directed CMEs were detected in
LASCO
imagery.July 20: A partial halo CME was observed after noon as a result of the
eruption of a large filament in the southeast quadrant.

Coronal holes

A recurrent trans equatorial coronal hole (CH232) was in an Earth
facing location on July 21-22. This coronal hole has decayed substantially over the
past two solar rotations and is currently poorly defined.

Processed SOHO/EIT 284 image at 01:06 UTC on July 23. The
darkest areas on the solar disk are likely coronal holes.

Forecast

The geomagnetic field is
expected to be quiet on July 23. The CME observed on July 20 could reach
Earth during the latter half of July 23 or on July 24 and cause unsettled to active conditions.
A low speed stream from CH232 could influence the geomasgnetic field on July
24-26 resulting in some unsettled intervals.

Coronal holes (1)

Coronal mass ejections (2)

M and X class flares (3)

1) Effects from a coronal hole could reach Earth
within the next 5 days. When the high speed stream has arrived the color changes to green.
2) Effects from a CME are likely to be observed at Earth within 96 hours.
3) There is a possibility of either M or X class flares within the next 48 hours.

Propagation

Long distance low and medium
frequency (below 2 MHz) propagation
along east-west paths over high and upper middle latitudes is poor. Propagation on long distance northeast-southwest paths
was fair to good during the night and very good during the first 90 minutes
after LSR. Propagation strongly favored stations from Argentina and Uruguay with
excellent signals from several stations (including 700, 710, 870, 930, 950,
1130, 1190, 1270, 1400, 1410 kHz). 1620 kHz had both Radio Vida and Radio Italia
with occasional good peaks, reaching signal levels not previously heard from
those stations.

Data for all numbered solar regions according to the Solar Region
Summary provided by NOAA/SEC. Comments are my own, as is the
STAR spot count (spots observed at or inside a few hours before
midnight) and data for regions not numbered by SEC or where SEC has observed no spots.
SEC active region numbers in the table below and in the active region
map above are the historic SEC/USAF numbers.

Active region

Date numbered

SEC
spot
count

STAR
spot
count

Location at midnight

Area

Classification

Comment

10900

2006.07.14

S06W65

plage

10901

2006.07.22

6

7

N06E70

0040

CSO

classification was DAO at midnight, area 0060

Total spot count:

6

7

SSN:

16

17

Monthly solar cycle data

Month

Average solar
flux at Earth

International sunspot number

Smoothed sunspot number

2000.04

184.2

125.5

120.8
cycle 23 sunspot max.

2000.07

202.3

170.1

119.8

2001.12

235.1

132.2

114.6 (-0.9)

2005.05

99.3

42.7

28.9 (-2.7)

2005.06

93.7

39.3

28.8 (-0.1)

2005.07

96.4

40.1

29.1 (+0.3)

2005.08

90.5

36.4

27.4 (-1.7)

2005.09

91.1

21.9

25.8 (-1.6)

2005.10

77.0

8.5

25.5 (-0.3)

2005.11

86.3

18.0

24.9 (-0.6)

2005.12

90.7

41.2

23.0 (-1.9)

2006.01

83.4

15.4

(20.7 predicted, -2.3)

2006.02

76.5

4.7

(18.2 predicted, -2.5)

2006.03

75.4

10.8

(16.4 predicted, -1.8)

2006.04

89.0

30.2

(15.7 predicted, -0.7)

2006.05

80.9

22.2

(14.9 predicted, -0.8)

2006.06

76.5

13.9

(12.7 predicted, -2.2)

2006.07

76.2 (1)

17.2 (2)

(11.3 predicted, -1.4)

1) Running average based on the
daily 20:00 UTC observed solar flux
value at 2800 MHz.
2) Unofficial, accumulated value based on the Boulder (NOAA/SEC)
sunspot number. The official international sunspot number is typically
30-50% lower.

This report has been prepared by Jan
Alvestad. It is based partly on my own observations and analysis, and
partly on data from some of these solar data sources.
All time references are to the UTC day. Comments and suggestions are always welcome.